243 
FXUS61 KCLE 240001
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
701 PM EST Mon Nov 23 2020

.SYNOPSIS...
High pressure will build east overnight and continue to New 
England Tuesday. Low pressure will track out of the southern 
Plains to near Chicago Wednesday, continuing northeast across 
the Great Lakes Region. Low pressure will move northeast out of
the Central Plains states Wednesday to the Central Great Lakes
Wednesday night. A ridge of high pressure will build east across
the Ohio Valley Friday afternoon and evening followed by another
ridge of high pressure that will build east across the area
Saturday.

&&

.NEAR TERM /THROUGH TUESDAY NIGHT/...
Removed slight chance/chance PoPs this evening/overnight as dry
air aloft begins to filter to the low-levels, evident by limited
returns on radar, including KCLE and TLVE. Instead, put isolated
sprinkles mention through 1 AM across NE OH and NW PA.
Otherwise, expecting a dry forecast overnight and through 
tomorrow morning.

Previous Discussion...
An upper level ridge is expected to move east across the eastern
United States tonight and off the East Coast Tuesday while
amplifying slightly. The amplification of the ridge is in
response to a digging upper level low pressure system and
associated trough into the Central Plains states by Tuesday
evening. Surface high pressure is expected to move east across
the area tonight. Some very weak lake effect bands continue
across northeast Ohio and northwest Pennsylvania and they are
struggling to survive as drier air, descending strong inversion,
and shear take place. Skies will make an attempt to go toward
clearing but this will end fairly quickly as surface low
pressure develops over the Plains States and moves northeast
toward the Central Great Lakes. This system will send moisture
our way during the day Tuesday and there will be a threat for
showers over the western portions of the area during the day
Tuesday. This activity will lift north across Lake Erie and then
some drier air will lift into the region for Tuesday night. At 
this time, the threat for precipitation Tuesday night will be
confined early to the lakeshore and then a small chance will begin
to push into the extreme west toward sunrise with the next storm
system.  As the high pressure moves east across the area, cold 
air advection will be waning allowing a return back to warm air 
advection for Tuesday and Tuesday night. Looking at temperatures 
dropping into the upper 20s to lower 30s across the area tonight, 
highs in the lower to middle 40s Tuesday, and lows in the middle 
to upper 30s Tuesday night.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
The short term forecast period will continue to have an active 
forecast as warm front will be north of the area and low pressure 
over the central Plains will propagate east into the region. The 
recent suite of guidance maintains Wednesday as the wet period as a 
good plume of moisture enters from the south, as transported by a 
modest 40-45 kt low level jet. With good upper level support, expect 
widespread rain activity on Wednesday and model soundings across the 
region show precipitable water values of 1 to 1.25 inches, which 
could be enough for some efficient rainfall for this time of year. 
Strong warm air advection could allow for temperatures to surge 
through the day on Wednesday, even with the rain, and highs into the 
50s are expected. 

The associated cold front will move through the region on Wednesday 
night and precipitation will clear from west to east and have PoPs 
decreasing as appropriate. High pressure will start building from 
the southwest behind the front for the Thanksgiving holiday and the 
forecast will be dry for much of the area. The area may sneak some 
early highs in the 50s before cooling off with some cold air 
advection through the day and then recovering once again as the 
surface high brings back some warmer temperatures, so a mix of 40s 
and 50s will be expected, if outdoors, which is above normal for 
late November.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
High pressure will be the theme for the first half of the long term 
period, which should keep the area dry through the first part of 
Sunday. Temperatures will remain a few degrees above normal for the 
end of the week. A potent upper trough and surface low appears to 
approach the region on Sunday and Monday and could bring the next 
widespread chance of rain. The extended guidance remains uncertain 
on the timing or placement of this surface feature and will keep 
generic chance PoPs for early next week with temperatures trending 
downward for the last day of November as the system will likely be 
gone by Monday night and colder air spreading in from the northwest.

&&

.AVIATION /00Z Tuesday THROUGH Saturday/...
VFR across the TAF sites this evening with mainly VFR to persist
through the TAF period. The exceptions are at ERI tonight, where
a brief period of MVFR ceilings are possible between 9-13Z, and
at TOL tomorrow afternoon where a brief period of MVFR
ceilings/vsbys are possible associated with rain and/or snow
showers. Otherwise, some vicinity rain showers are possible at
FDY/MFD/CLE tomorrow afternoon but are not expected to cause any
flight restrictions at this time.

West to northwest winds, 5 to 10 knots across the area this
evening with higher winds, 10 to 15 knots along the lakeshore
mainly impacting ERI. Winds will shift more southerly tomorrow,
5 to 10 knots, across the TAF sites.

Outlook...Non-VFR possible with rain on Wednesday, and low
ceilings through Thursday night. Non-VFR ceilings may persist
across Northeast Ohio and Northwest Pennsylvania during the day
Friday. 

&&

.MARINE...
High pressure entering the Great Lakes region this evening has 
allowed for winds to subside over Lake Erie. High waves of 4 to 5 ft 
will continue over the next several hours and will keep the Small 
Craft Advisory up as is to account for this threat. Light winds will 
continue through Tuesday as high pressure will become centered over 
the lake. A low pressure system over the central United States on 
Tuesday night will lift a warm front through the region and strong 
southerly winds will overtake the lake. While winds will be 
offshore, a Small Craft Advisory is not out of the question as 
southerlies will try to exceed 20 knots. Low pressure will continue 
along this front on Wednesday night and cross the lake on Thursday. 
This will allow for winds to become more southwesterly over the 
basin and some higher waves may build over the eastern basin, which 
could prompt a Small Craft Advisory. High pressure will attempt to 
rebuild into the region on Friday and winds will lessen over the 
lake, becoming more onshore for the weekend.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
MARINE...Small Craft Advisory until 2 AM EST Tuesday for LEZ146>149.
     Small Craft Advisory until 10 PM EST this evening for LEZ144-
     145.

&&

$$
SYNOPSIS...Lombardy
NEAR TERM...Kahn/Lombardy
SHORT TERM...Sefcovic
LONG TERM...Sefcovic
AVIATION...Kahn
MARINE...Sefcovic